Twelve Month Interim Report. Volume II. Oncogenic Potential Of Vinyl Bromide During Chronic Inhalation Exposure.
Huntingdon Research Center, New York, New York, Project No. 7511-253, 1977 Feb:225 pages
The oncogenic potential of vinyl-bromide (593602) (VBr) during chronic inhalation exposure in rats was determined. Sections of selected tissues were exposed to 50, 250, and 1,250 parts per million (ppm) VBr, 6 hours per day for 5 days a week and for a period of 6 months. A similar set of tissues from controls exposed to filtered air was also examined microscopically. No consistent exposure related microscopic alterations were observed in any of the tissues examined from rats exposed to the three concentrations of VBr. A relatively low incidence of incidental microscopic lesions was observed in both control and exposed rats. A few scattered cases of non suppurative, interstitial nephritis were observed in kidneys from a few rats in both groups. Bone marrow activity was within expected normal limits and was comparable among control and exposed groups. Lungs were relatively free of inflammatory lesions, and only a few scattered incidental microscopic alterations were observed in the lungs of controls and exposed rats. A squamous cell carcinoma of the ear was observed in a rat exposed to 250ppm. A lymphosarcoma was present in the spleen, bone marrow, and liver of a rat exposed to 50ppm. The author concludes that the 6 month exposure of rats to 50, 250, and 1,250ppm VBr does not result in any histologic alterations in tissues examined.
NIOSH-Contract; Animal-studies; Dose-response; Medical-research; Histopathology; Toxicopathology; Carcinogenicity; Biological-effects; Comparative-toxicology;
NTIS Accession No.
Huntingdon Research Center, New York, New York, Project No. 7511-253, 225 pages